There could be a couple of reasons that another player has a troop higher stats/ skills than you.

On Consoles:
They could be using the correct kingdom banner for the troop, which will be giving stats/skill points to all Adana troops.
(I’m not sure where consoles versions are up to so I can’t answer more than this.)

On PC/iOS/Mobile:
They could have multiple kingdoms at level 10.
They could have created a team that get team bonuses (whether Adana or Construct).
The troop could be higher than level 15.
There may be traits unlocked that boost it’s stats.